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+/*
+ Copyright (C) 2014 Matthias P. Braendli (http://www.opendigitalradio.org)
+
+ This program is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published by
+ the Free Software Foundation, either version 3 of the License, or
+ (at your option) any later version.
+
+ This program is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see <http://www.gnu.org/licenses/>.
+
+ dabplussnoop.cpp
+ Parse DAB+ frames from a ETI file
+
+ Authors:
+ Matthias P. Braendli <matthias@mpb.li>
+*/
+
+/* From the spec:
+
+subchannel_index = MSC sub-channel size (kbps) / 8
+audio_super_frame_size (bytes) = subchannel_index * 110
+
+// Derived from
+// au_start[n] = au_start[n - 1] + au_size[n - 1] + 2;
+// 2 bytes for CRC
+au_size[n] = au_start[n+1] - au_start[n] - 2;
+
+he_aac_super_frame(subchannel_index)
+{
+ he_aac_super_frame_header()
+ {
+ header_firecode 16
+ rfa 1
+ dac_rate 1
+ sbr_flag 1
+ aac_channel_mode 1
+ ps_flag 1
+ mpeg_surround_config 3
+
+ // end of audio parameters
+ if ((dac_rate == 0) && (sbr_flag == 1)) num_aus = 2;
+ // AAC core sampling rate 16 kHz
+ if ((dac_rate == 1) && (sbr_flag == 1)) num_aus = 3;
+ // AAC core sampling rate 24 kHz
+ if ((dac_rate == 0) && (sbr_flag == 0)) num_aus = 4;
+ // AAC core sampling rate 32 kHz
+ if ((dac_rate == 1) && (sbr_flag == 0)) num_aus = 6;
+ // AAC core sampling rate 48 kHz
+
+ for (n = 1; n < num_aus; n++) {
+ au_start[n]; 12
+ }
+
+ if !((dac_rate == 1) && (sbr_flag == 1))
+ alignment 4
+ }
+
+ for (n = 0; n < num_aus; n++) {
+ au[n] 8 * au_size[n]
+ au_crc[n] 16
+ }
+
+}
+*/
+
+#include <stdio.h>
+#include <stdint.h>
+#include <stdlib.h>
+#include <string.h>
+#include <string>
+#include <sstream>
+#include <vector>
+#include "faad_decoder.hpp"
+
+#ifndef __DABPLUSSNOOP_H_
+#define __DABPLUSSNOOP_H_
+
+
+class DabPlusSnoop
+{
+ public:
+ DabPlusSnoop() :
+ m_index(0),
+ m_subchannel_index(0),
+ m_data(0),
+ m_raw_data_stream_fd(NULL) {}
+
+ void set_subchannel_index(unsigned subchannel_index)
+ {
+ m_subchannel_index = subchannel_index;
+ }
+
+ void set_index(int index)
+ {
+ m_index = index;
+ }
+
+ void push(uint8_t* streamdata, size_t streamsize);
+
+ void close(void);
+
+ private:
+ /* Data needed for FAAD */
+ FaadDecoder m_faad_decoder;
+ int m_index;
+
+ bool m_ps_flag;
+ bool m_aac_channel_mode;
+ bool m_dac_rate;
+ bool m_sbr_flag;
+ int m_mpeg_surround_config;
+
+ /* Functions */
+
+ bool seek_valid_firecode(void);
+ bool decode(void);
+ bool extract_au(std::vector<int> au_start);
+ bool analyse_au(std::vector<std::vector<uint8_t> >& aus);
+
+ unsigned m_subchannel_index;
+ std::vector<uint8_t> m_data;
+
+ FILE* m_raw_data_stream_fd;
+};
+
+#endif
+